24-38 AIR-CONDITIONING-Service Adjustment Procedures
(4) Purge the air from the charging line by loosening the charging
hose at the gauge set manifold and turning one of the refrig-
erant valves counterclockwise to release refrigerant. When
the refrigerant gas starts escaping from the loose connection,
re-tighten the hoses.
Caution
Never heat small refrigerant cans over 52°C (125°F) as they
mad explode.
(5) qully open all refrigerant manifold valves being used and place
the cans of refrigerant into a pan containing 52°C (125°F) water
will warm the charging can and aid in the transfer of the charge
into the system. Place the water pan and refrigerant cans on
a scale and note the weight.
(6) Jump the low pressure switch terminals located on the re-
ceiver drier so the clutch will remain engaged.
(7) Start the engine and move the controls to air conditioner
switch on and low blower position.
The low pressure switch will prevent the clutch from engaging
until refrigerant is added to the system. If the clutch does
engage, replace the switch before proceeding any further.
(8) Charge through the suction side of the system by slowly open-
ing the suction manifold valve. Adjust the valve as necessary
so charging pressure does not exceed 345 kPa (50 psi).
Maintain the temperature of the water in the pan by adding
warm water as necessary. Note the weight of water
added, to ensure accuracy when determining amount of
refrigerant added to system.
(9) Adjust the engine speed to a fast idle of approximately 1500
rpm.
(IO) When specified refried refrigerant charge 730 (1.6 Ibs.) has
entered the system, close the gauge set manifold valves,
refrigerant manifold valves, and reconnect wiring. Each
can contains 397 g (14 oz.) of R-12. Use 2 l/2 cans.
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